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APPROVED VENDOR Sealing Washer: M21 Screw Sz, Copper, Copper Seal, 21 mm Inside Dia, 28 mm Outside Dia - Single-Piece Sealing Washers
APPROVED VENDORSingle-Piece Sealing Washers

APPROVED VENDOR Sealing Washer: M21 Screw Sz, Copper, Copper Seal, 21 mm Inside Dia, 28 mm Outside Dia

The APPROVED VENDOR Single-Piece Sealing Washer (SKU 54FP80) is a copper seal washer for M21 screw sizes, with a 21 mm inside diameter and 28 mm outside diameter. Supplied in a 25-pack, this metric copper seal washer…

SKU 3G-OTH-534513

Brand
APPROVED VENDOR
Item
Sealing Washer: M21 Screw Sz, Copper, Copper Seal, 21 mm Inside Dia, 28 mm Outside Dia
Category
Single-Piece Sealing Washers
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
M50301.210.0028
Type
Copper, Copper Seal, 25 PK
Pack Size
Small Pack
Inside Dia
21 mm
Outside Dia
28 mm
Product Type
Sealing Washer
Seal Material
Copper
System of Measurement
Metric
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APPROVED VENDOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The APPROVED VENDOR Single-Piece Sealing Washer (SKU 54FP80) is a copper seal washer for M21 screw sizes, with a 21 mm inside diameter and 28 mm outside diameter. Supplied in a 25-pack, this metric copper seal washer (MPN M50301.210.0028) is a straightforward sealing component for industrial applications.

Frequently Asked Questions

What is an APPROVED VENDOR copper sealing washer used for?

This copper sealing washer is used to create a leak-proof seal under bolt heads or nuts in metric M21 fasteners. It is common in hydraulic, pneumatic, and plumbing systems where vibration or thermal cycling could loosen standard washers. Copper's malleability ensures a tight, durable seal.

What are the specifications of the APPROVED VENDOR M50301.210.0028 sealing washer?

This sealing washer has a 21 mm inside diameter and 28 mm outside diameter, designed for M21 screw sizes. It is made of copper, supplied in a 25-pack small pack. The system of measurement is metric, and the manufacturer part number is M50301.210.0028.

Where to buy APPROVED VENDOR sealing washers worldwide?

3G Electric supplies APPROVED VENDOR sealing washers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for availability and lead time on this copper sealing washer for M21 screws.

How to install a copper sealing washer for M21 screws?

Place the copper sealing washer over the M21 bolt or stud before tightening. Ensure the washer sits flat against the mating surface. Tighten to the manufacturer's torque specification; copper deforms slightly to fill gaps. Do not reuse copper washers as they lose sealing ability after compression.

Used in

Common applications for APPROVED VENDOR
Laboratory sampling — APPROVED VENDOR clear wide mouth glass bottles for collecting and storing liquid samples in non-sterile environments.
Steam heating maintenance — APPROVED VENDOR forged brass radiator valves for regulating steam flow in commercial building heating systems.
High-pressure cleaning — APPROVED VENDOR turbo spray nozzles for pressure washers used in industrial equipment cleaning up to 6,000 psi.
Cleanroom operations — APPROVED VENDOR vinyl task chairs for seating in ISO 5 classified manufacturing or assembly areas.
General sealing — APPROVED VENDOR natural rubber stoppers for closing laboratory flasks or test tubes in educational or research settings.
Tamper-evident security — APPROVED VENDOR brass lead and wire seals for securing utility meters, cargo containers, or access panels.

APPROVED VENDOR Products

3G Electric supplies APPROVED VENDOR single-piece sealing washers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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